Boiler



H. B. ALDRICH Jan. 14, 1 941.

BOILER Filed Feb. 27,

Patented Jan. 14, 1941 UNITED STATES PATENT OFFICE i BOILER Application February 27, 1940, Serial No. 320,989

Z Claims.

This invention relates to boilers, and it relates more particularly to boilers, of the type used for heating buildings and the like, which are made of a plurality of hollow cast iron sections, vertically disposed, and connected to each other by suitable nipples.

The principal object of the present invention is to provide a boiler, of the character aforesaid, which is so constructed and arranged as to obtain a high heat transfer efficiency.

A further object of the invention is to provide a boiler, of the character aforesaid, which will be simple in construction, but in which the gases of combustion will be thoroughly agitated and caused to be brought into intimate contact with the various surfaces of the boiler sections.

A further object of the invention is to provide a boiler, of the character aforesaid, in which a free flow of the gases of combustion to the flue will be permitted, thus rendering the boiler available for economical use even where a poor draft is provided by reason of faulty or insufficient chimney construction,

With the foregoing objects in view, the invention contemplates the provision, in each section of a cast iron sectional boiler, of a plurality of tubes disposed horizontally, and in communication with each other, which tubes however are so arranged as to cause a thorough agitation of the ascending gases to bring them into intimate contact with the various surfaces of the several sections and this without unduly obstructing the free passage of said gases to the flue.

35 'Ihe boiler of the present invention is adapted for either coal or oil firing.

The nature and characteristic features of the invention will be more readily understood from the following description, taken in connection D with the accompanying drawing forming part hereof, in which Figure 1 is a vertical central sectional view of a boiler embodying the main features of the present invention;

45 Fig. 2 is a vertical section taken transversely to Fig. 1, one of the intermediate sections of the boiler being shown in elevation;

Fig. 3 is a horizontal section taken on the line 3--3 of Fig. l; and

50 Fig. 4 is a horizontal section taken on the line 4-4 of Fig. 2.

It should, of course, be understood that the description and drawing herein are illustrative merely and that various changes and modifica- 55 tions may be made in the structure disclosed without departing from the spirit of the invention.

Referring to the drawing, in the particular embodiment of the invention therein shown, the boiler proper comprises a plurality of Sections 5 vertically disposed, each made of cast iron or the like, and connected to each other in a manner to be hereinafter set forth.

The particular boiler shown in the drawing consists of four such sections, to-witz-a front 'l0 section A, two intermediate sections B, and a rear section C. When it is desired to increase the capacityof the boiler, this is ordinarily done by increasing the number of the intermediate sections. l5

Each of the intermediate sections B is provided, at the lower portion thereof, with vertically depending hollow water legs Ii) which are enlarged at the bottom, as at II to enable the connection nipples I2 to be mounted therein. The c0nnec 20 tion nipples I2 are each of the usual tubular form tapered externally from the center toward each end.

The medial portion of each of the intermediate sections B is so formed as to provide horizontal 25 water tubes I3 extending from` side to side, communicating at each end to extensions of the leg portions IU. The horizontal Water tubes I3 are preferably each of polygonal cross section, in the nature of a flattened hexagon.

The horizontal water tubes I3 are connected to each other by hollow vertical tubular portions I4 providing water passages which are disposed in a staggered arrangement as shown in Fig. 2 of the drawing, thereby permitting a free circulation of the water contained within the various hollow portions of the casting.

Each of the sections is also provided at its upper portion with a hollow chamber I5 which serves as a steam space when the boiler is used 40 in low pressure steam heating systems, or which will be lled with water when the boiler is used in hot water heating systems. The upper portion of each intermediate section B is provided on each face thereof with an aperture for the mounting therein of the upper connection nipples I6.

The front section A is substantially similar to that of the intermediate sections B, with the exception that the same is suitably shaped to provide for the door openings in the front of the boiler, and in the front face at the top, instead of the tapered aperture for the reception of the connection nipple I6 there is a corresponding aperture I'I suitably threaded for the connection of 55 an outlet pipe. This threaded aperture may be closed by a suitable plug I8 when the pipe connection is made at the rear of the boiler.

The rear section C is also shaped similarly to the intermediate sections B, with the exception that in addition to the other parts, there is provided a hollow portion I9 in the lower part connecting with the side legs IU of said section C to provide a water wall at the rear of the combustion chamber.

As shown in Fig. 3 of the drawing the return circulation pipe 20 is connected to a threaded opening in the lower part of the water Wall I9. Said opening may be centrally disposed as shown or, if preferred, two return pipes may be used, each connected with the rearmost section C at the bottom of one of the side legs and in alinement with the connection nipples I2.

The outlet pipe 2| may be connected to a threaded aperture in the central part of the rearmost section, near the top thereof, as shown in Fig. 1 of the drawing, although here again a plurality of outlet pipes may be provided, if desired, connected at the side portions of the section C at the upper part thereof.

The several sections of the boiler are held together by means of a bolt 22 extending from front to rear at the top, and two similar bolts 23 extending from front to rear at the bottom.

The horizontal water tubes I3 in the medial portion of each of the several sections of the boiler are each of a width less than that of the section, and the same are alternately offset on each side of the medial plane of the section thereby to provide, when the several sections are assembled, a series of tortuous vertical paths for the gases of combustion rising from the combustion chamber, as shown in Fig. l of the drawing.

By the foregoing arrangement of the horizontal tubes, the combustion gases are caused to be agitated and to impinge against the various surfaces of the tubes and other portions of the sections; yet at the same time no undue restriction is placed upon the upward movement of the gases toward the flue.

At the top of the boiler there is provided a dome casting 24 extending over the several sections of the boiler, and having at the top a connection nipple 25 for the attachment thereto of the usual ilue pipe (not shown).

The boiler sections are preferably enclosed by a box-like arrangement of slabs 26 of heat insulating material, which will serve to prevent undue radiation of heat in the vicinity of the boiler and, at the same time, give the same a pleasing appearance.

The several sections of the boiler are supported on a suitable base framework 21, of box-like formation, to provide an ash-pit, when the boiler is to be used for coal firing, or to provide additional combustion space when the boiler is oll fired.

I claim:

1. A boiler comprising a plurality of hollow cast sections connected to each other at the top, each of said sections having a water leg on each side in the lower portion thereof thereby to provide a combustion chamber therebetween, the water legs of each section being connected to the water legs of adjacent sections at the bottom, each of said sections having a plurality of horizontal water tubes polygonal in cross section formed in the medial portion thereof, said horizontal water tubes each being of a width less than the section and alternately offset on each side of the medial plane of the section thereby to provide tortuous vertical paths for the gases of combustion, the adjacent horizontal water tubes in eachsection being connected to each other intermediate their ends by vertical connections disposed within the respective sections and at points offset from each other, and the rear section having a hollow portion extending downwardly from the lowermost horizontal water tube of said section and between and connecting the leg portions thereof, said hollow portion forming a water Wall at the rear of the combustion chamber.

2. A boiler comprising a plurality of hollow cast sections connected to each other at the top, each of said sections having a water leg on each side in the lower portion thereof thereby to provide a combustion chamber therebetween, the water legs of each section being connected to the Water legs of adjacent sections at the bottom, each of said sections having a plurality of horizontal water tubes polygonal in cross section formed in the medial portion thereof, said horizontal water tubes each being of a width less than the section and alternately offset on each side of the medial plane of the section thereby to provide tortuous vertical paths for the gases of combustion, the adjacent horizontal water tubes in each section being connected to each other .intermediate their ends by vertical connections disposed Within the respective sections at points offset from each other, the rear section having a hollow portion extending downwardly from the lowermost horizontal water tube of said section and between and connecting the leg portions thereof, said' hollow portion forming a water wall at the rear of the combustion chamber, and the boiler sections being supported on a box frame the interior of which is in open communication with the combustion chamber.

HERBERT B. ALDRICH. 

